Marnie Chesterton

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Still to come, what is El Niño and how did the ancient Moche civilisation in Peru try and deal with it?

That's after this.

Hello again, Lucy here, back with the answer to this week's quiz.

Earlier, I asked you how do new mice mothers warn male mice to stay away from their babies?

A. Banana-scented urine.

B. Orange-coloured sweat.

Or C. A circle of berries around their nest.

The answer is A, banana-scented urine.

Scientists discovered a banana-scented chemical in the urine of pregnant and recently pregnant mice called amyl acetate.

When exposed to it, male mice showed unusually high levels of stress, probably because, according to the researchers, this chemical means, if you come any closer, I will beat you up, which I think would stress anyone out.

Although, given that male mice often eat the babies of other mice, I'd say the aggressive messaging is probably warranted.

So, if you come across a stressed out new mum who seems to be leaving a banana-scented aroma in her wake, maybe give her some space?

For both your sakes.

Now it's time in the show where we use everything in our powers to try and answer those tricksy science questions that AI tools just won't answer.

Think of us as scientific matchmakers, pairing your musing to an expert who's really put in the years to finding the answer to your question.

It's time for Ask the Unexpected.

And our question this week comes from a regular listener of the show, Liz from London.

Liz's dying houseplants got her thinking about how plants in the wild die.